Find the probability that at least two operating rooms are used.

Question

The following data were collected by counting the number of operating rooms in use at Tampa General Hospital over a 20-day period: On four of the days only one operating room was used, on six of the days two were used, on eight of the days three were used, and on two days all four of the hospital's operating rooms were used.

x: f(x)

1 .2

2 .3

3 .4

4 .1

total 1

Answer 1

P(at least two operating rooms are used)=

P(X>=2) = P(X=2) + P(X=3) +P(X=4)

= 0.3+0.4+0.1

= 0.8